Propagation mode analysis of rotating detonation waves fueled by liquid kerosene

The propagation modes of rotating detonation waves supplied with liquid kerosene and oxygen-enriched air were experimentally investigated. Experiments were conducted while maintaining the equivalence ratio at approximately 0.7 and varying the mass flow rate of the oxidizer from 585.3 to 1493.8 g/s. Three propagation modes were obtained, and the propagation characteristics of rotating detonation waves in each mode were extensively analyzed. The results reveal that for the test model with an equivalence ratio of 0.7, the rotating detonation waves exhibit three types of modes in sequence as the mass flow rate of the oxidizer increases, namely, single-wave mode, single/dual-wave hybrid mode, and dual-wave mode. The propagation modes of rotating detonation waves vary randomly in the single/dual-wave hybrid mode, and the mode transition processes are more likely to be accompanied by transient detonation wave extinction due to the lower activity of liquid kerosene. For the single/dual-wave hybrid mode, the pressure feedback of rotating detonation waves to oxidizer plenum in the single-wave mode is greater than that in the dual-wave mode, which is related to the higher pressure peaks of rotating detonation waves in the single-wave mode. Moreover, the relative standard deviation of the propagation frequency is calculated to evaluate the propagation stability of the rotating detonation wave. It was found that the rotating detonation waves possess higher propagation stability in the dual-wave mode than in the single-wave mode.